1. Technical Field
The present invention relates to methods of manufacturing Group III-V compound semiconductor substrates.
2. Description of the Related Art
III-V compound semiconductor substrates are manufactured by slicing off substrates from an ingot, and polishing and thereafter cleaning the substrate surfaces. (Cf. Japanese Unexamined Pat. App. Pub. No. H05-291231.)
Polishing the surface of a III-V compound semiconductor substrate, however, subjects the surface to damage. As a consequence, the substrate's photoluminescence intensity (PL intensity) is degraded. Forming semiconductor devices on the surface of a III-V compound substrate that carries damage is a futile exercise, if outstanding device characteristics are sought.
Given that polishing produces superficial damage on III-V compound substrates, the present inventors investigated dry-etching the post-polished surface as a means of removing the damage-affected material. The results of their investigations confirmed improvement in the PL intensity of III-V compound substrates. Nevertheless, further improvement in III-V semiconductor substrate PL intensity is being sought, in order yield prevailing superior device characteristics.